Knee Surgery and Related Research最新文献

{"title":"The preoperative flexion tear gap affects postoperative meniscus stability after pullout repair for medial meniscus posterior root tear.","authors":"Masanori Tamura, Takayuki Furumatsu, Takahiro Kitayama, Yusuke Yokoyama, Yuki Okazaki, Koki Kawada, Toshifumi Ozaki","doi":"10.1186/s43019-025-00264-7","DOIUrl":"10.1186/s43019-025-00264-7","url":null,"abstract":"<p><strong>Background: </strong>We investigated whether the preoperative flexion tear gap (FTG) observed in open magnetic resonance imaging (MRI) affects meniscus stability after medial meniscus (MM) posterior root (MMPR) repairs. Furthermore, time-correlated MRI findings from MMPR tear occurrence were evaluated.</p><p><strong>Methods: </strong>This retrospective observational study included 54 patients (mean age, 64.6 years; 13 males and 41 females) who underwent pullout repair for radial degenerative MMPR tear. Meniscus stability (scored 0-4 points) was assessed using a semi-quantitative arthroscopic scoring system during second-look arthroscopy 1 year postoperatively. The FTG was evaluated on preoperative axial MRI at 90° knee flexion. Other MRI measurements included MM extrusion (MME) at 10° knee flexion, MM posterior extrusion (MMPE) at 90° knee flexion, and MM posteromedial extrusion (MMpmE) at 90° knee flexion preoperatively and 1 year postoperatively. The correlation between the arthroscopic stability score and MRI findings was investigated. A receiver-operating characteristic curve was calculated to predict a good meniscus healing score (3-4 points). The correlation between the FTG and patient demographics, including time from injury to MRI, was analyzed.</p><p><strong>Results: </strong>At 1 year postoperatively, MME increased by 1.1 mm, while MMpmE and MMPE decreased by 0.4 mm and 1.0 mm, respectively. The meniscus stability score was negatively correlated with the preoperative FTG (r = -0.61, p < 0.01). The time from injury to MRI was significantly correlated with the preoperative FTG. The receiver-operating characteristic curve identified an FTG cut-off value of 8.7 mm for predicting good postoperative stability, with sensitivity and specificity of 67% and 85%, respectively.</p><p><strong>Conclusions: </strong>FTG evaluated with open MRI at 90° knee flexion was associated with time from injury and affected meniscus stability following pullout repair. MMPR tears should be treated in the early phase to increase meniscus healing stability.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"16"},"PeriodicalIF":0.0,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11969855/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143781222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intraarticular leukocyte-poor platelet-rich plasma injection is more effective than intraarticular hyaluronic acid injection in the treatment of knee osteoarthritis: a systematic review and meta-analysis of 12 randomized controlled trials.","authors":"Yu-Ning Peng, Yu-Hsiang Peng, Jean-Lon Chen, Carl P C Chen","doi":"10.1186/s43019-025-00266-5","DOIUrl":"https://doi.org/10.1186/s43019-025-00266-5","url":null,"abstract":"<p><strong>Purpose: </strong>We aim to compare the clinical effects of intraarticular leukocyte-poor platelet-rich plasma (LP-PRP) injection with those of intraarticular hyaluronic acid (HA) injection in adult patients with knee osteoarthritis.</p><p><strong>Methods: </strong>Two authors independently reviewed databases, including PubMed, Web of Science, and the Cochrane Library. Only randomized controlled trials (RCTs) were included in our meta-analysis. Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores (WOMAC total, pain, stiffness, and physical function scores), visual analog scale (VAS) scores, EQ-VAS scores, International Knee Documentation Committee (IKDC) scores, and adverse events were used as outcome measurements to evaluate the efficacy of LP-PRP and HA treatment.</p><p><strong>Results: </strong>After screening 377 potential articles, 12 RCTs were included in this systemic review and meta-analysis. The WOMAC total scores and WOMAC physical function scores of the LP-PRP group were better than those of the HA group at 6 and 12 months. VAS scores of the LP-PRP group were better than those of the HA group at 3, 6, and 12 months. The LP-PRP group showed a better outcome of IKDC scores than the HA group at 6 months. There was no significant difference in adverse events between the LP-PRP and HA groups.</p><p><strong>Conclusion: </strong>Intraarticular injections of LP-PRP showed better overall outcomes, such as WOMAC total scores, WOMAC physical function scores, VAS scores, and IKDC scores, compared with HA for adult patients with knee osteoarthritis at 6- and 12-month follow-up periods. Also, LP-PRP showed better pain relief compared with HA at 3-, 6-, and 12-month follow-up periods. Intraarticular LP-PRP improves pain relief and overall outcomes in patients with knee osteoarthritis.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"15"},"PeriodicalIF":0.0,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11951639/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143744267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Total knee arthroplasty in patients with degenerative spine disease: does spinal fusion affect outcomes? A matched comparative analysis using a national database.","authors":"Mohammad Daher, Jonathan Liu, Alan H Daniels, Eric M Cohen, Valentin Antoci, Mouhanad M El-Othmani","doi":"10.1186/s43019-025-00267-4","DOIUrl":"10.1186/s43019-025-00267-4","url":null,"abstract":"<p><strong>Background: </strong>The need for total knee arthroplasty (TKA) and spinal fusion (SF) for degenerative spine disease (DSD) is increasing. However, it is still unknown if prior SF for DSD impacts outcomes following TKA. This study aims to fill this gap by comparing the risk of complications and revisions in patients undergoing TKA with DSD between patients with and without SF.</p><p><strong>Methods: </strong>This study is a retrospective review of the PearlDiver Mariner Database between 2010 and 2020. On the basis of whether or not patients had had prior SF, the patients undergoing TKA were divided into two groups: patients with DSD and SF and patients with DSD and without SF. The two groups were matched on the basis of age, gender, the Charlson Comorbidity Index (CCI), and obesity. Surgical complications (mechanical loosening, prosthetic dislocation, periprosthetic fractures, and stiffness) and revisions at 1, 2, and 3 years were compared between the groups.</p><p><strong>Results: </strong>The patients in the TKA with DSD and no SF cohort were older (64.9 ± 8.4 versus 63.3 ± 8.1 years, p < .001), had higher CCI (2.0 ± 2.2 versus 1.6 ± 2.0, p < .001), and had a lower rate of obesity (58.7% versus 61.7%, p < .001). After being matched, 8887 patients remained in each group. There was a higher rate of stiffness and manipulation under anesthesia (MUA) in the no-fusion cohort at 1 year (0.7% versus 0.1%, p < .001; and 0.5% versus 0.2%, p < .001, respectively), 2 years (1.2% versus 0.5%, p < .001; and 1.1% versus 0.6%, p < .001, respectively), and 3 years (1.7% versus 0.7%, p < .001; and 1.6% versus 0.9%, p < .001, respectively).</p><p><strong>Conclusions: </strong>This study shows no increase in risk of surgical complications and revisions after TKA in patients with DSD and SF compared with patients without SF. Notably, SF was shown to be protective of stiffness and MUA after TKA in patients with DSD.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"14"},"PeriodicalIF":0.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11931872/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143701712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of central sensitization on perioperative pain in TKA: a retrospective cohort study.","authors":"Tatsuru Sonobe, Takuya Nikaido, Miho Sekiguchi, Yoichi Kaneuchi, Tadashi Kikuchi, Yoshihiro Matsumoto","doi":"10.1186/s43019-025-00263-8","DOIUrl":"10.1186/s43019-025-00263-8","url":null,"abstract":"<p><strong>Background: </strong>Total knee arthroplasty (TKA) is an established surgical procedure for severe knee osteoarthritis (KOA) that has provided excellent outcomes. While several studies have reported that patients with preoperative central sensitization (CS) experienced worse pre- and post-operative pain and outcomes, the evidence is limited. We conducted this study to determine the impact of CS on perioperative knee pain in TKA for severe KOA.</p><p><strong>Methods: </strong>A retrospective cohort study of 66 patients who underwent bilateral TKA for bilateral severe KOA was conducted. Multiple linear regression models that included covariates and scaled estimated regression coefficients were used to examine the impact of CS on the patients' pre- and post-operative pain subscale values on the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the improvement of KOOS pain. Postoperative KOOS pain was assessed at 3 months postoperatively, while other evaluation items including preoperative KOOS pain, CS, and pain self-efficacy were assessed on admission.</p><p><strong>Results: </strong>CS had a negative impact on pre- and post-operative KOOS pain (preoperative, β: -0.28, 95% confidence interval [CI] -18.53, -0.92; postoperative, β: -0.26, 95%CI -14.09, -0.44; p < 0.05). High pain self-efficacy had a positive impact on preoperative KOOS pain (β: 0.25, 95%CI 0.32, 18.08; p < 0.05). However, CS did not influence the improvement of KOOS pain.</p><p><strong>Conclusions: </strong>These results demonstrate that CS had a negative impact on pre- and post-TKA knee pain in patients but did not affect the improvement of knee pain. TKA provides sufficient pain relief for severe KOA, with or without CS. Further research is required to improve pre- and post-operative knee pain in KOA patients with CS.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"13"},"PeriodicalIF":0.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11921699/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143664874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sarcopenia: how to determine and manage.","authors":"Jun Young Chung, Sang-Gyun Kim, Seong Hwan Kim, Cheol Hee Park","doi":"10.1186/s43019-025-00265-6","DOIUrl":"10.1186/s43019-025-00265-6","url":null,"abstract":"<p><strong>Background: </strong>Understanding sarcopenia is becoming increasingly important as society ages. This comprehensive review covers the definition, epidemiology, causes, pathogenesis, diagnosis, prevention, management, and future directions for the management of sarcopenia, and the major issues related to sarcopenia in the knee joint.</p><p><strong>Main text: </strong>Sarcopenia, a condition related to aging, is characterized by decreased muscle mass and strength, which significantly affects physical function. Its prevalence may vary by region and age, with reports of up to 50% prevalence in the elderly population. The potential causes of sarcopenia include neurodegeneration, poor nutrition, changes in hormonal effects, elevated levels of proinflammatory cytokines, and reduced activation of muscle satellite cells. Various pathogeneses, such as apoptosis, proteolysis, and inhibition of the signaling for increasing muscle mass, contribute to the development of sarcopenia. Generally, the diagnostic criteria for sarcopenia are based on reduced muscle mass, reduced muscle strength, and decreased physical performance, and can be assessed using various equipment and clinical tests. A healthy lifestyle consisting of a balanced diet, sufficient protein intake, and regular exercise is recommended to prevent sarcopenia. The management of sarcopenia involves resistance exercise, proper nutrition, and deprescribing from polypharmacy. In the future, pharmacological treatment and personalized nutrition may become alternative management options for sarcopenia. Finally, since sarcopenia can be associated with knee osteoarthritis and poor outcomes after total knee arthroplasty, appropriate management of sarcopenia is important for physicians treating knee-related conditions.</p><p><strong>Conclusions: </strong>Sarcopenia is a significant pathological condition that needs to be recognized, especially in the older population. Although sarcopenia is common as aging occurs, it can be prevented by a healthy lifestyle. Currently, there are no approved drugs for sarcopenia; however, resistance exercise and proper nutritional supplementation are essential methods for managing sarcopenic conditions. Given its diverse causes, a personalized approach may be necessary to effectively manage sarcopenia. Finally, appropriate management of sarcopenia can contribute to the prevention and effective treatment of knee osteoarthritis.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"12"},"PeriodicalIF":0.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11912661/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tibial morphological difference between metal augmentation and actual tibia for revision total knee arthroplasty.","authors":"Yushi Sakamoto, Shinichiro Nakamura, Yugo Morita, Shinichi Kuriyama, Kohei Nishitani, Sayako Sakai, Yuki Shinya, Shuichi Matsuda","doi":"10.1186/s43019-025-00262-9","DOIUrl":"10.1186/s43019-025-00262-9","url":null,"abstract":"<p><strong>Background: </strong>An overhang of the tibial component can cause irritation of the surrounding soft tissues, whereas an underhang is associated with risks of tibial bone resorption. It is not well known whether the tapering angle of currently available blocks at medial, lateral, anterior, and posterior sides matches the actual shape of the proximal tibia. The purpose of this study was to analyze the bony contour of the proximal tibia and measure the tapering angle to examine whether the angle of currently available metal augmentation blocks matches the actual tibia.</p><p><strong>Methods: </strong>Computed tomography of the lower extremities was performed on 100 consecutive knees, and three-dimensional images of the tibia were reconstructed. The primary resection level was determined on the basis of a plane 10 mm below the center of the lateral tibial plateau. The assumed levels were set to 5, 10, 15, and 20 mm below the primary resection level. All points that were 5, 10, 15, or 20 mm below were projected onto the primary resection surface, and the reduction value from the primary level to each level was measured. The tapering angle was calculated on the basis of the reduction value from the primary level to each resection surface at eight areas and compared with the angle of currently available metal augmentation acquired from the company. The distances of mismatch between the metal augmentation and the bone surface were calculated.</p><p><strong>Results: </strong>The tapering angle on the medial and lateral sides increased with the more distal resection level, which was up to 30° at the 20 mm level. The tapering angle on the posterior side also increased with the more distal resection level, which was approximately 40° at the 20 mm level. The tapering angle of the current implant was smaller than that of the original tibial morphology. The distances of mismatch varied between implants in which the maximum distance was up to 11.3 mm in the 15 mm augmentation.</p><p><strong>Conclusions: </strong>The design of current metal augmentation differs from the morphology of the proximal tibia. Surgeons should pay attention to the size mismatch between the femoral and tibial components during revision total knee arthroplasty (TKA).</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"10"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11874112/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143543765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Do knee alignment patterns differ between Middle Eastern and East Asian populations? A propensity-matched analysis using artificial intelligence.","authors":"Jisoon Park, Oussama Chaar, Jayakrishnan Narayanakurup, Alamedin Sobhe Abdelsamea Abdelhamead, Du Hyun Ro, Sung Eun Kim","doi":"10.1186/s43019-025-00261-w","DOIUrl":"10.1186/s43019-025-00261-w","url":null,"abstract":"<p><strong>Introduction: </strong>Population-based differences in knee alignment patterns may impact osteoarthritis (OA) progression. This study compares lower extremity alignment in knee OA between Middle Eastern (UAE) and East Asian (South Korean) populations using artificial intelligence (AI)-assisted analysis.</p><p><strong>Methods: </strong>A retrospective review included patients with knee symptoms from South Korea (2009-2019) and the United Arab Emirates (UAE) (2015-2024). Exclusion criteria comprised prior knee surgeries, significant bony attrition, and low-quality radiographs. Propensity score matching controlled for age and sex differences between populations. Alignment parameters (hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), and joint line convergence angle (JLCA)) and OA severity (Kellgren-Lawrence (KL) grade) were measured using artificial intelligence (AI) software, along with the analysis of coronal plane alignment of the knee (CPAK) classification. Subanalyses by sex and age group (under 40, 40-60, and over 60 years) were also conducted.</p><p><strong>Results: </strong>A total of 1098 UAE and 7138 South Korean patients (2196 and 14,276 knees, respectively) were evaluated in this study. Post-matching (1:2), body mass index was significantly higher in UAE patients (p < 0.001). CPAK type 1 was predominant in UAE male patients (42.4%), whereas type 2 was more common in South Korean male patients (30.6%). Female patients in both populations predominantly exhibited CPAK type 2 (UAE 30.6%; South Korea 35.3%). UAE patients showed a lower MPTA with increasing age, indicating a trend toward more varus alignment in older individuals.</p><p><strong>Conclusions: </strong>A propensity score-matched analysis revealed significant alignment differences between Middle Eastern and East Asian populations, underscoring the importance of population-specific considerations in OA management.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"11"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11877683/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143543762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"McMurray's test is influenced by perimeniscal synovitis in degenerative meniscus tears.","authors":"Yong Jun Jin, Jae-Young Park, Jun Young Chung, Sujin Noh, Hee-Woong Yun, Sumin Lim, Do Young Park","doi":"10.1186/s43019-024-00242-5","DOIUrl":"10.1186/s43019-024-00242-5","url":null,"abstract":"<p><strong>Background: </strong>McMurray's test is a useful physical examination in determining meniscus tears, yet its sensitivity is only 38-62%. Furthermore, the relationship between degenerative meniscus tears (DMT) and mechanical symptoms during McMurray's test is not well defined. Perimeniscal synovitis occurs in osteoarthritic (OA) knees, inducing localized symptoms such as posterior knee pain in medial meniscus posterior horn DMTs. This study aimed to determine the relationship between McMurray's test with medial meniscus DMT and perimeniscal synovitis in patients with knee OA.</p><p><strong>Methods: </strong>We retrospectively analyzed 60 patients who underwent medial unicompartmental knee arthroplasty (UKA) with positive (n = 20) and negative (n = 40) preoperative McMurray's tests. Preoperative magnetic resonance imaging (MRI), intraoperative gross morphology, and histological analysis of meniscus and synovium were evaluated to determine meniscal tears and perimeniscal synovitis. Univariate and multivariate regression analyses were done to determine the effects of meniscus tears and synovitis on McMurray's test results.</p><p><strong>Results: </strong>Gross morphology of the medial meniscus (MM) showed 14 out of 20 torn menisci in the McMurray's (+) group compared with 22 out of 40 in the (-) group, with no difference in meniscus tear severity among groups. The (+) group showed higher values of synovial thickness (p < 0.001) and area (p < 0.001) compared with the (-) group on magnetic resonance imaging (MRI). Histological analysis showed higher synovitis (p < 0.001) scores and expression of inflammatory markers [interleukin (IL)-1β (p < 0.001), IL-6 (p = 0.007), nerve growth factor (NGF) (p = 0.003), inducible nitric oxide synthase (iNOS) (p < 0.001)] in the perimeniscal synovium of (+) group compared with the (-) group. Multivariable logistic analysis revealed that larger synovial area [odds ratio (OR) = 1.106, p = 0.008] and a higher histologic synovitis score (OR = 2.595, p = 0.011) were independently significant predictive factors for a positive McMurray's test.</p><p><strong>Conclusions: </strong>McMurray's test may be influenced by perimeniscal synovitis in DMT patients. The clinical implications of our results may influence not only the interpretation of McMurray's test but also the target tissue in treating mechanical symptoms related to meniscus tears.</p><p><strong>Level of evidence: </strong>Level II.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"9"},"PeriodicalIF":0.0,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11871708/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143531976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Caliper verification and gap measurements of kinematic alignment total knee arthroplasty utilizing an imageless, accelerometer-based navigation system.","authors":"James H Sikes, Drew P Melancon, Isaac J Spears, Evan H Powers, Spencer J Montgomery","doi":"10.1186/s43019-025-00260-x","DOIUrl":"10.1186/s43019-025-00260-x","url":null,"abstract":"<p><strong>Purpose: </strong>Kinematic alignment (KA) in total knee arthroplasty (TKA) aims to restore the patient's knee to the prearthritic state. The purpose of this study was to investigate the accuracy of using an implant-agnostic, imageless, accelerometer-based navigation system to perform KA TKA on the basis of caliper verification and quantification of the flexion and extension gaps.</p><p><strong>Materials and methods: </strong>Seven cadaveric lower extremities underwent primary TKA utilizing a kinematic alignment workflow with the imageless navigation system. Accuracy of the technique was confirmed through caliper verification of bone cuts.</p><p><strong>Results: </strong>All cuts were within 1 mm of anticipated measurements, except for the lateral tibial fragment, which averaged 1 mm (standard deviation [SD] 0.9 mm) thicker than anticipated. In extension, medial and lateral gaps were symmetric and averaged within 0.6 mm of expectation. In flexion, the medial gap averaged within 0.5 mm of expectation, while the lateral gap averaged 2.6 mm larger than the symmetric expectation, consistently producing a trapezoidal space.</p><p><strong>Conclusions: </strong>The implementation of an accelerometer-based navigation system in KA TKA allows for highly accurate results, which was confirmed with caliper verification. This workflow produced a symmetric extension gap and a trapezoidal flexion gap with an average increased lateral flexion gap of 2.6 mm compared with the medial side.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"8"},"PeriodicalIF":0.0,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11834236/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143441840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between muscle activation and sagittal knee joint biomechanics in patients with patellofemoral pain syndrome: a cross-sectional study.","authors":"Byung Sun Choi, Soon Bin Kwon, Sehyeon Jeon, Myeongjun Kim, Yunseo Ku, Du Hyun Ro, Hyuk-Soo Han","doi":"10.1186/s43019-025-00259-4","DOIUrl":"10.1186/s43019-025-00259-4","url":null,"abstract":"<p><strong>Background: </strong>Patellofemoral pain syndrome (PFPS) is one of the most common conditions affecting the knee joint, yet its pathomechanics remain unclear. The aim of this study was to investigate changes in muscle activation and gait patterns and to analyze the relationship between muscle activation and kinetic gait patterns in patients with PFPS.</p><p><strong>Methods: </strong>This study included 31 patients with PFPS and 28 healthy volunteers without any symptoms. The sagittal plane motion of the knee joint, representing primary movement of the knee joint, was evaluated to identify changes in gait patterns. Electromyography (EMG) was used to measure muscle activation of vastus medialis (VM), vastus lateralis (VL), semitendinosus (ST), and gastrocnemius (GCM) muscles during gait analysis. Biomechanical features were analyzed during the three phases of the gait cycle; weight acceptance (WA), single limb support (SLS), and swing limb advancement (SLA) (0 ~ 12%, 13 ~ 50%, and 51 ~ 100% of the gait cycle, respectively).</p><p><strong>Results: </strong>The average knee extension moment (KEM) during WA was lower in the patient group and no significant differences were observed in the knee flexion angle (KFA). With respect to muscle activation, the patient group showed significantly higher muscle activation of the ST muscle in all phases. As the absolute value of the moment increased, the activation of the VM, VL, and ST muscles increased more rapidly in the patient group, especially when KEM was under -1% body weight × height (Bw × Ht) or over 5% Bw × Ht.</p><p><strong>Conclusions: </strong>Patients with PFPS exhibit elevated muscle activation, particularly in response to changes in the knee extension moment, which is likely a compensatory mechanism to manage knee joint loading during gait. These results highlight altered neuromuscular adaptations in PFPS, suggesting targeted therapies may help improve functional outcomes. Level of evidence III, cross-sectional study.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"7"},"PeriodicalIF":0.0,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11763116/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143042275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}